The present invention relates to a projection lens system of a projector apparatus.
Japanese Laid-Open Patent Publication No. 2006-215476 discloses a compact, wide-angle projection lens system that is suited to a light modulator, such as a DMD, equipped with a plurality of elements that generate an image by changing the direction of reflection of light. Publication No. 2006-215476 states that by using a arrangement where a negative first lens group and a positive second lens group are disposed in that order from the screen side, where the incident side is non-telecentric, where a pair of doublet cemented lenses with positive refractive power and with the cemented surfaces facing in opposite directions are disposed on the screen side of the second lens group, and where a triplet cemented lens with positive refractive power is disposed on the light valve side, it is possible to effectively correct curvature of field and provide a wide-angle projection lens system that is compact and has a half angle of view of 47 degrees or wider.
In applications such as presentations and education, there is demand for a projection lens system that is more compact and is even wider.